1. Technical Field
The present invention relates generally to semiconductor manufacturing and related technologies. More particularly, the present invention relates to electron beam apparatus for use in lithography or inspection tools.
2. Description of the Background Art
The present disclosure provides a novel and inventive electron source which has use in either electron beam lithography or automated electron beam inspection (or review) systems.
As is known in the art, electron beam lithography systems may be categorized as electron beam direct write (EBDW) or electron beam projection systems. In EBDW lithography, the substrate is sequentially exposed by means of a focused electron beam, wherein the beam either scans in the form of lines over the whole specimen and the desired structure is written on the object by corresponding blanking of the beam, or, as in a vector scan method, the focused electron beam is guided over the regions to be exposed. The beam spot may be shaped by a diaphragm. In electron beam projection lithography, analogously to optical lithography, a larger portion of a mask is illuminated simultaneously and is imaged on a reduced scale on a wafer by means of projection optics. Since a whole field is imaged simultaneously in electron beam projection lithography, the attainable throughputs can be markedly higher in comparison with electron beam writers.
As is also known, automated electron beam inspection (or review) systems may be classified as either scanning or projection systems. Scanning electron beam systems are more commonplace and operate by scanning an electron beam across a region of a substrate surface to obtain image data. On the other hand, projection electron beam systems operate by simultaneously projecting a wider electron beam over a larger area and by using a position-sensitive detection system to detect data for an array of pixels in parallel.